Predictors of nonfunctional arteriovenous access at hemodialysis initiation and timing of access creation: A registry-based study.

Determinants of nonfunctional arteriovenous (AV) access, including timing of AV access creation, have not been sufficiently described. We studied 29 945 patients who had predialysis AV access placement and were included in the French REIN registry from 2005 through 2013. AV access was considered nonfunctional when dialysis began with a catheter. We estimated crude and adjusted odds ratio (OR) with 95% confidence intervals (CI) of nonfunctional versus functional AV access associated with case-mix, facility characteristics, and timing of AV access creation. Analyses were stratified by dialysis start condition (planned or as an emergency) and comorbidity profile. Overall, 18% patients had nonfunctional AV access at hemodialysis initiation. In the group with planned dialysis start, female gender (OR 1.43, 95% CI 1.32-1.56), diabetes (OR 1.28, 95% CI 1.15-1.44), and a higher number of cardiovascular comorbidities (OR 1.27, 95% CI 1.09-1.49, and 1.31, 1.05-1.64, for 3 and >3 cardiovascular comorbidities versus none, respectively) were independent predictors of nonfunctional AV access. A higher percentage of AV access creation at the region level was associated with a lower rate of nonfunctional AV access (OR 0.98, 95% CI 0.98-0.99 per 1% increase). The odds of nonfunctional AV access decreased as time from creation to hemodialysis initiation increased up to 3 months in nondiabetic patients with fewer than 2 cardiovascular comorbidities and 6 months in patients with diabetes or 2 or more such comorbidities. In conclusion, both patient characteristics and clinical practices may play a role in successful AV access use at hemodialysis initiation. Adjusting the timing of AV access creation to patients' comorbidity profiles may improve functional AV access rates.

Vascular access conversion and patient outcome after hemodialysis initiation with a nonfunctional arteriovenous access: a prospective registry-based study.

BACKGROUND: Little is known about vascular access conversion and outcomes for patients starting hemodialysis with nonfunctional arteriovenous (AV) access. We assessed mortality risk associated with nonfunctional AV access at hemodialysis initiation, taking subsequent changes in vascular access into account. METHODS: We studied the 53,092 incident adult hemodialysis patients included in the French REIN registry from 2005 through 2012. AV access placed predialysis was considered nonfunctional when dialysis began with a central venous catheter. Information about vascular access changes was obtained from treatment modality updates. RESULTS: At hemodialysis initiation, AV access was functional for 47% of patients and nonfunctional for 9%; 44% had a catheter alone. After a 3-year follow-up, 63% of patients beginning hemodialysis with a nonfunctional AV access had changed to a functional one, 4% had had a transplant, 19% had died before any vascular access change, and 13% still used a catheter. Cox proportional hazard models with vascular access treated as a time-dependent variable showed an adjusted mortality hazard ratio (95% confidence interval) for patients with nonfunctional AV access who subsequently converted to functional access of 0.95 (95% CI 0.89-1.03) compared with the reference group with functional AV access since first hemodialysis, versus 1.43 (95% CI 1.31-1.55) for those who did not convert. CONCLUSIONS: Among patients starting hemodialysis with a nonfunctional AV access, a substantial percentage may never experience successful vascular access conversion. Poor survival seems to be limited to these patients, while those who subsequently convert to functional AV access have similar mortality risk compared to patients with such access since hemodialysis initiation. Every effort should be made to obtain functional AV access in all suitable patients.

Economic impact of a modification of the treatment trajectories of patients with end-stage renal disease.

BACKGROUND: This study assumed that some patients currently treated at hospital-based haemodialysis centres can be treated with another renal replacement therapy (RRT) modality without any increase in mortality risk and sought to evaluate the monthly cost impact of replacing hospital-based haemodialysis, for which fees are highest, by different proportions of other modalities. METHODS: We used a deterministic model tool to predict the outcomes and trajectories of hypothetical cohorts of incident adult end-stage renal disease (ESRD) patients for 15 years of RRT (10 different modalities). Our estimates were based on data from 67 258 patients in the REIN registry and 65 662 patients in the French national health insurance information system. Patients were categorized into six subcohorts, stratified for age and diabetes at ESRD onset, and analyses run for each subcohort. We simulated new strategies of care by changing any or all of the following: initial distributions in treatment modalities, transition rates and some costs. Strategies were classified according to their monthly per-patient cost compared to current practices (cost-minimization analysis). RESULTS: Simulations of the status quo for the next 15 years predicted a per-patient monthly cost of €2684 for a patient aged 18-45 years without diabetes and €7361 for one older than 70 years with diabetes. All of the strategies we analysed had monthly per-patient costs lower than the status quo, except for daily home HD. None impaired expected survival. Savings varied by strategy. CONCLUSIONS: Alternative strategies may well be less expensive than current practices. The decision to implement new strategies must nonetheless consider the number of patients concerned, feasibility of renal care reorganization, and investment costs. It must also take into account the role of patients' choice and the availability of professionals.

Survival advantage of hemodialysis relative to peritoneal dialysis in patients with end-stage renal disease and congestive heart failure.

Peritoneal dialysis (PD) has been proposed as a therapeutic option for patients with end-stage renal disease and associated congestive heart failure (CHF). Here, we compare mortality risks in these patients by dialysis modality by including all patients who started planned chronic dialysis with associated congestive heart failure and were prospectively enrolled in the French REIN Registry. Survival was compared between 933 PD and 3468 hemodialysis (HD) patients using a Kaplan-Meier model, Cox regression, and propensity score analysis. The patients were followed from their first dialysis session and stratified by modality at day 90 or last modality if death occurred prior. There was a significant difference in the median survival time of 20.4 months in the PD group and 36.7 months in the HD group (hazard ratio, 1.55). After correction for confounders, the adjusted hazard ratio for death in PD compared to the HD patients remained significant at 1.48. Subgroup analyses showed that the results were not changed with regard to the New York Heart Association stage, age strata, or estimated glomerular filtration rate strata at first renal replacement therapy. The use of propensity score did not change results (adjusted hazard ratio, 1.55). Thus, mortality risk was higher with PD than with HD among incident patients with end-stage renal disease and congestive heart failure. These results may help guide clinical decisions and also highlight the need for randomized clinical trials.

Confounding factors for early death in incident end-stage renal disease patients: Role of emergency dialysis start.

Hemodialysis (HD) has been associated with higher 1-year mortality than peritoneal dialysis (PD) after dialysis start. Confounding effects of late referral, emergency dialysis start, or start with central venous catheter on this association have never been studied concomitantly. Survival was studied among the 495 incident dialysed patients in our department from 1995 to 2006 and followed at least 1 year until December 31, 2007. Nested Cox models adjusted on patient characteristics explored factors associated with 1-year and ≥1-year mortality. Hemodialysis patients were 332 (67.1%), 104 (21.0%) were late referred (<6 months), 167 (33.7%) started dialysis in emergency, and 144 (29.1%) started with central venous catheter. When adjusted only on age, sex, and comorbidities, HD was associated with poor 1-year outcome: adjusted hazard ratio (aHR) for death in HD vs. PD was 1.77, P=0.02. In fully adjusted model, among first dialysis feature variables, only emergency dialysis start was significantly associated with 1-year mortality: aHR 1.53, P=0.02. Dialysis modality was not associated with 1-year mortality rates in this fully adjusted model: aHR in HD vs. PD became 1.03, P=0.91. In ≥1-year period, HD was associated with lower mortality than PD (aHR 0.61, P=0.004), whereas other first dialysis features were not associated with death. Other factors associated with death were age, type 2 diabetes, peripheral vascular disease, heart failure, and hepatic failure. Negative association between HD and 1-year survival on dialysis was explained by confounders. Emergency dialysis start was strongly associated with early mortality on dialysis. Its prevention may improve patient survival.

Age and comorbidity may explain the paradoxical association of an early dialysis start with poor survival.

Starting patients on dialysis early has been increasing in incidence in several countries. However, some studies have questioned its utility, finding a counter-intuitive effect of increased mortality when dialysis was started at a higher estimated glomerular filtration rate (eGFR). To examine this issue in more detail we measured mortality hazard ratios associated with Modification of Diet in Renal Disease eGFR at dialysis initiation for 11,685 patients from the French REIN Registry, with sequential adjustment for a number of covariates. The eGFR was analyzed both quantitatively by 5-ml/min per 1.73 m(2) increments and by demi-decile (i.e., 5 percentiles of the distribution); the 15th demi-decile, including values around 10 ml/min per 1.73 m(2), was our reference point. The patients more likely to begin dialysis at a higher eGFR were older male patients; had diabetes, cardiovascular diseases, or low body mass index and level of albuminemia; or were started with peritoneal dialysis. During a median follow-up of 21.9 months, 3945 patients died. The 2-year crude survival decreased from 79 to 46%, with increasing eGFR from less than 5 to over 20 ml/min per 1.73 m(2). Each 5-ml/min/1.73 m(2) increase in eGFR was associated with a 40% increase in crude mortality risk, which weakened to 9%, but remained statistically significant after adjusting for the above covariates. Analysis by demi-decile showed only the highest to be at significantly higher risk. Hence we found that age and patient condition strongly determine the decision to start dialysis and may explain most of the inverse association between eGFR and survival.

A clinical score to predict 6-month prognosis in elderly patients starting dialysis for end-stage renal disease.

AIM: The aim of this study was to develop and validate a prognostic score for 6-month mortality in elderly patients starting dialysis for end-stage renal disease. METHODS: Using data from the French Rein registry, we developed a prognostic score in a training sample of 2500 patients aged 75 years or older who started dialysis between 2002 and 2006, which we validated in a similar sample of 1642 patients. Multivariate logistic regression with 500 bootstrap samples allowed us to select risk factors from 19 demographic and baseline clinical variables. RESULTS: The overall 6-month mortality was 19%. Age was not associated with early mortality. Nine risk factors were selected and points assigned for the score were as follows: body mass index <18.5 kg/m2 (2 points), diabetes (1), congestive heart failure stages III to IV (2), peripheral vascular disease stages III to IV (2), dysrhythmia (1), active malignancy (1), severe behavioural disorder (2), total dependency for transfers (3) and unplanned dialysis (2). The median score was 2. Mortality rates ranged from 8% in the lowest risk group (0 point) to 70% in the highest risk group (> or =9 points) and 17% in the median group (2 points). Seventeen percent of all deaths occurred after withdrawal from dialysis, ranging from 0% for a score of 0-1 to 15% for a score of 7 or higher. CONCLUSIONS: This simple clinical score effectively predicts short-term prognosis among elderly patients starting dialysis. It should help to illuminate clinical decision making, but cannot be used to withhold dialysis. It ought to only be used by nephrologists to facilitate the discussion with the patients and their families.

[Specificities of the methodology of survival analysis in dialysis patients]. / Spécificités méthodologiques de l'analyse de survie des patients dialysés.

Epidemiological and observational studies are needed in nephrology for evidence-based medical decision and global knowledge of renal patients. Using strong methodology, such studies are useful to formulate hypotheses for further explanatory studies or clinical trials. Survival analysis of dialysis patients are based on the usual and robust Kaplan-Meier and Cox regression methods. Nevertheless, their use should take into account the specificities of the dialysis population, especially when non-constant risks for death with time and sub-groups analyses are considered. In addition, survival curves from birth or standardised mortality ratio are able to provide a new view of survival by changing of analytical perspective. Our aim is to summarize the specificities of survival study methodology in dialysis patients using concrete examples in French cohorts.

Associations between comorbidities, treatment choice and outcome in the elderly with end-stage renal disease.

BACKGROUND: New patients treated for end-stage renal disease are increasingly elderly: in France, 38% are 75 years or older. The best treatment choices for the elderly are still debated. METHODS: We studied case-mix factors associated with choice of initial dialysis modality and 2-year survival in the 3512 patients aged 75 years or older who started dialysis between 2002 and 2005 and were included in the French REIN registry. RESULTS: Overall, 18% began with peritoneal dialysis (PD), 50% with planned haemodialysis (planned HD) and 32% with unplanned HD, that is, HD that started on an emergency basis. At least one comorbid condition was reported for 85%, and three or more for 36%, but case-mix varied with age. PD was chosen significantly more often than planned HD for the oldest (> or =85) compared with the youngest (75-79) patients: odds ratio 2.1 (95% confidence interval, 1.5-2.8), in those with congestive heart failure: 1.8 (1.5-2.3) and severe behavioural disorder: 2.2 (1.3-3.5), but less often for obese patients: 0.5 (0.3-0.8) and smokers: 0.4 (0.2-0.9). Two-year survival rates were 58, 52 and 39% in patients aged 75-79, 80-84 and > or =85, respectively. Compared with planned HD, unplanned HD was associated with a risk of mortality 50% higher, and PD with a risk 30% higher, independent of patient case-mix. CONCLUSION: PD is a common treatment option in French elderly patients, but our study suggests the need for caution in the long-term use. The high frequency of unplanned HD would require further attention.

Effect of age, gender, and diabetes on excess death in end-stage renal failure.

Life expectancy is short in elderly individuals with end-stage renal failure (ESRF). This study aimed to compare mortality in patients with ESRF versus the general population (GP) to assess the evolution of excess mortality by age, gender, nephropathy, and dialysis modality after first dialysis. All incident adult dialysis patients from January 1,1999, to December 31, 2003, who lived in Rhône-Alpes Region (France) were included and followed up to death or December 31, 2005. Standardized mortality ratios (SMR) in comparison with GP were computed in the first to the fifth years after first dialysis. In the whole cohort (3025 incident patients), SMR decreased during these 5 yr from 7.4 to 5.2 (P = 0.002). In the 18- to 44-, 45- to 64-, 65- to 74-, 75- to 84-, and > or =85-yr-old groups, SMR decreased from 26.7 to 6.2 (P = 0.01), from 12.8 to 8.1 (P = 0.03), from 8.6 to 5.6 (P = 0.051), from 7.1 to 4.5 (P = 0.02), and from 3.5 to 1.2 (P = 0.14), respectively. Among age categories, differences were significant in the first 3 yr (P < 0.05). SMR were higher 1.5-fold in women than in men in the first 4 yr (P < 0.05). In patients with diabetic nephropathy (DN), SMR increased during the first 3 yr (P = 0.045) and were higher than in patients without DN in the second, third, and fourth years (P < 0.05). SMR were higher in the peritoneal dialysis than in the hemodialysis group in the fourth year (P < 0.01). Patients with ESRF have a high excess mortality compared with the GP. Older patients with ESRF experienced less excess mortality. ESRF cancels out women's survival advantage noted in the GP. SMR evolution in patients with DN was different from that in patients without DN.

Poor prognosis of heart transplant patients with end-stage renal failure.

BACKGROUND: Chronic kidney disease (CKD) and end-stage renal failure (ESRF) are major complications after a heart transplant. The aim of this study is to compare survival in heart transplant (HT) vs non-heart transplant (non-HT) patients starting dialysis. METHODS: Survival was studied among the 539 newly dialysed patients between 1 January 1995 and 31 December 2005 in our Department. All patients were prospectively followed from the date of first dialysis up to death or 31 December 2005. Multivariate survival analysis adjusted on baseline characteristics was performed with the Cox model. RESULTS: There were 21 HT patients and they were younger than non-HT patients at first dialysis: 58.6+/-11.6 vs 63.0+/-16.2 years (P=0.09). Calcineurin inhibitor nephrotoxicity was the main cause of ESRF in HT patients (47.6%). Crude 1, 3 and 5-year survival rates in HT and in non-HT patients were as follows: 76.2%, 57.1%, 28.6% and 79.1%, 58.7%, 46.7% (P=0.2). The adjusted hazard ratio of death in HT vs non-HT patients was 2.27 [1.33-3.87], P=0.003. Sudden death was the main cause of death in HT patients, in 33.3% vs 10.4% in non-HT patients (P=0.01). Five HT patients benefited from renal transplant. They were all alive at the end of the study period, while one patient among the 16 remaining on dialysis survived. CONCLUSION: HT patients with CKD who reached ESRF have a poor outcome after starting dialysis in comparison with other ESRF patients. Improvement in renal function management in the case of CKD is needed in these patients and non-nephrotoxic immunosuppressive regimens have to be evaluated. Renal transplant should be the ESRF treatment of choice in HT patients.

The renal epidemiology and information network (REIN): a new registry for end-stage renal disease in France.

The French Renal Epidemiology and Information Network (REIN) registry began in 2002 to provide a tool for public health decision support, evaluation and research related to renal replacement therapies (RRT) for end-stage renal disease (ESRD). It relies on a network of nephrologists, epidemiologists, patients and public health representatives, coordinated regionally and nationally. Continuous registration covers all dialysis and transplanted patients. In 2003, 2070 patients started RRT, 7854 were on dialysis and 7294 lived with a functioning graft in seven regions (with a population of 16.5 million people). The overall crude annual incidence rate of RRT for ESRD was 123 per million population (p.m.p.) with significant differences in age-adjusted rates across regions, from 84 [95% confidence interval (CI): 74-94] to 155 [138-172] p.m.p. The principal causes of ESRD were hypertension (21%) and diabetic (20%) nephropathies. Initial treatment for ESRD was peritoneal dialysis for 15% of patients and a pre-emptive graft for 3%. The one-year survival rate was 81% [79-83] in the cohort of 2002-2003 incident patients. As of December 31, 2003, the overall crude prevalence was 898 [884-913] p.m.p, with 5% of patients receiving peritoneal dialysis, 47% on haemodialysis and 48% with a functioning graft. The experience in these seven regions over these two years clearly shows the feasibility of the REIN registry, which is progressively expanding to cover the entire country.

A multicentre study of registration on renal transplantation waiting list of the elderly and patients with type 2 diabetes.

BACKGROUND: Studies in the USA have shown that some patients (African-Americans, women, the elderly and diabetics) were less likely to receive renal transplants. In order to identify patient characteristics modifying the likelihood of being wait-listed, we studied registration on renal transplantation waiting list (WLR) focusing on elderly (age > or =60 years) and on patients with type 2 diabetes (D2) in three departments of nephrology in the Rhône-Alpes county in France. METHODS: In a cohort of 549 patients who reached end-stage renal disease (ESRD) between 1995 and 1998 in these units, we analysed the rates of pre-transplant evaluation (PTE), the duration of PTE, the rates of exclusion from transplantation by PTE and the rates of WLR. With Cox regression model, we identified the characteristics that have independent and significant effects on the likelihood of being registered after the first renal replacement therapy (RRT). RESULTS: In this cohort, 185 patients (33.7%) were wait-listed by 31.03.00 and no patient > or =70 years was evaluated or registered. In univariate analysis, PTE and WLR rates were lower in the elderly (21.5 and 20.0%, respectively) than those <60 years (79.1 and 70.2%, P < 0.001) and in D2 (33.0 and 24.2%) than in non-D2 (65.8 and 60.6%, P < 0.001). The duration of PTE was longer in D2 than in non-D2 (12.7 +/- 11.0 vs 7.5 +/- 7.1 months, P < 0.01). Among patients excluded from PTE, more patients without relevant co-morbidities [e.g. rapidly progressive ESRD, cardiovascular disease (CVD), malignancy] were present in the elderly (> or =70 years: 14.8%; 60-69 years: 17.0%; <60 years: 6.4%) and in D2 (18.0%) than in non-D2 (10.9%). The adjusted relative risks (aRR) of being wait-listed after first RRT were significantly lowered by age and D2 (aRR, 95% CI): 60-64 year olds (0.44%: 0.26-0.75), 65-69 year olds (0.07%: 0.03-0.20) and D2 (0.41%: 0.24-0.69). Other conditions associated with a lower aRR were rapidly progressive ESRD (0.21%: 0.08-0.55), CVD (0.59%: 0.36-0.94), malignancy (0.13%: 0.04-0.46) and psychosis (0.05%: 0.01-0.35). CONCLUSION: Advanced age and D2 were associated with low PTE and WLR rates even after adjustment for other patient characteristics.